Microcos latifolia Burret

Chung, R. C. K. & Soepadmo, E., 2011, Taxonomic revision of the genus Microcos (Malvaceae-Grewioideae) in Peninsular Malaysia and Singapore, Blumea 56 (3), pp. 273-299 : 289

7. Microcos latifolia Burret — Fig. 9 ; Map 7

Microcos latifolia Burret (1926) 781; R.C.K. Chung et al. (2005b) 111. — Grewia latifolia Mast. in Hook.f. (1874) 392, non G. latifolia F.Muell. ex Benth.(1863) 271; King (1891) 112;Ridl.(1922) 300.— Grewia blattaefolia Corner (1939) 262; Kochummen (1973) 399; (1997) 429; Corner (1988) 733; Keng (1990) 88. — Microcos blattaefolia (Corner) R.S.Rao (1949) 300, p.p.; I.M.Turner (1993) 221; (1997) 487. — Lectotype ( Chung et al. 2005b): Maingay 3150 (holo K), Peninsular Malaysia, Malacca.

Small tree to 15 m tall, dbh to 20 cm; buttresses absent. Outer bark smooth, lenticellate, brown or reddish brown with greenish patches; inner bark pale brown or brown, fibrous; sapwood white. Twigs striate, greyish brown, densely covered with tufted hairs. Stipules unlobed, oblong, 3–7 by 2 – 4 mm, apex obtuse, densely covered with tufted hairs on both sides, caducous or persistent. Leaves brown to dark brown on both sides, coriaceous, glabrous or densely covered with simple and tufted hairs on midrib and secondary veins above, densely covered with simple and tufted hairs or glabrescent beneath; petioles (6–)8 –16(–19) mm long, 2– 2.5(– 3) mm thick, brown to dark brown, apically not swollen, densely covered with tufted hairs; blade narrowly or broadly elliptic, equilateral or sometimes inequilateral, (10 –)13– 27(–30) by (4–)5 –10(–12) cm, base cuneate or obtuse to rounded, margin entire and uneven, not ciliate, apex obtuse, acute or acuminate, acumen 1–2 cm long with a pointed tip; midrib and secondary veins impressed or raised above, raised beneath; secondary veins 6 – 9 pairs, basal pair reaching between 0.25 and 0.5 of blade length, forming an angle of 45° with the midrib; domatia absent; tertiary veins reticulate, inconspicuous above, conspicuous or obscure beneath. Inflorescences Type B panicles, terminal or axillary, (2–) 3.5–8 cm long, densely covered with tufted hairs; bracts unlobed, narrowly elliptic or obovate, 1.5– 4.5(– 5.5) by 0.3 –1.5(–3.5) mm, densely covered with tufted hairs on both sides, caducous or occasionally persistent; involucral bracts of outer whorl 4 –5.5 mm long, 2 – 3-parted or 2– 3-divided, lobes lanceolate, 2.5– 4 mm long, apex acute, smooth outside, densely covered with tufted hairs on both sides, that of inner whorl oblanceolate, 3.5 – 4 by 1–1.8 mm, apex obtuse or obliquely truncate, densely covered with tufted hairs on both sides. Flower buds broadly obovoid, 3 – 5.5 by 2– 4 mm, densely covered with tufted hairs; pedicels 0.8–1 mm long, c. 1 mm thick, densely covered with tufted hairs; sepals oblanceolate, 5.5– 8 by 1–1.5 mm, densely covered with tufted hairs outside, sparsely covered with tufted hairs inside; petals 5, broadly ovate, 1.5– 3 by 1–1.5 mm, apex acute or obtuse, outside densely covered with tufted hairs at base to c. 0.5 of its length and sparsely covered with glandular trichomes towards the apex, inside densely covered with tufted hairs around the glands to c. 0.75 of its length and glabrous towards the apex; glands obloid or broadly obovoid; androgynophore concave in outline, 1–1.3(–2) mm long, 0.8 –1(–1.5) mm diam, shallowly longitudinally grooved, glabrous or sparsely covered with tufted hairs only on the ridges, apical part not expanded outwards, with undulate rim covered with tufted hairs; stamens with filaments 2.5–4(–5) mm long, glabrous, anthers c. 0.1 mm diam; ovary (1–)3-locular with internal ridges covered with tufted hairs directly opposite the placenta, subglobose or obloid, 1.2 –1.5 mm diam, oblate in cross section, densely covered with tufted hairs; style 2.5 –3.5(–4) mm long, occasionally glabrous or covered with tufted hairs at base to reaching between 0.25 and 0.5 of its length and glabrous towards the apex. Infructescences sparsely covered with tufted hairs. Fruits obovoid, smooth, 1.5– 2(–2.5) by 1–1.5(–1.8) cm, drying brown to dark brown, initially sparsely covered with tufted hairs, becoming glabrous; apex rounded, without pseudostalk; exocarp brittle or membranous; mesocarp 1.5– 3 mm thick; endocarp 1–2(–2.5) mm thick, woody. Pyrenes 3, partly connate; fertile pyrene 1, 1-seeded, 8 –10 mm long; sterile pyrene 2, conspicuous; pyrenes arranged horizontally or occasionally triangularly, with the fertile one larger than the sterile pyrenes.

Distribution — Peninsular Malaysia, Singapore and Borneo (confined to Sarawak and Brunei).

Habitat & Ecology — In lowland and hill mixed dipterocarp forests, to 600 m altitude. Flowering: January, March – October; fruiting: January, April, July–December.

Vernacular names — Chenderai gajah, damak-damak bulu, tajam damak (Malay).

Uses — Ripe fruits edible.

Figures

Map 7 Distribution of Microcos latifolia Burret in Peninsular Malaysia and Singapore.

Fig. 9 Microcos latifolia Burret. a. Flowering leafy twig; b. flower buds surrounded by involucral bracts; c. longitudinal section of flower bud; d. flower with sepals and petals removed; e. abaxial surface of petal; f. adaxial surface of petal with gland at base; g. cross section of ovary; h. stigma; i. fruit; j. longitudinal section of fruit; k. cross section of fruit (a –c, g: Yeop FMS 9497; d–f, h: Griffith 638/1; i –k: Ahmad Zainuddin et al. AZ 3901). Drawn by M. Nizam, UKMB (a, e, f) and by J. Pao, SAR (b–d, g–k).